Although Ken Kesey was initially involved in the film adaptation of his 1962 novel, he left the production after just two weeks and took a law suit out against the film's producers. Kesey's grievances were numerous but most notably he wanted Gene Hackman, not Jack Nicholson, to play Randle McMurphy. The author was also incensed that Chief Bromden (played by Will Sampson) was not the narrator in the film, as he is in the novel. One lovely story goes that Kesey mistakenly stumbled across the film on television many years later, and was enjoying what he saw, but hurriedly switched channels when he realised what he was watching.

Incensed: Ken Kesey felt his novel had been 'butchered' (AP)

2. One Flew Over the Cuckoo's Nest is one of only three films to win all five major Academy Awards

It won the Oscar for (deep breath): Best Picture, Best Director, Best Actor, Best Actress and Best Adapted Screenplay. The other films to have done the same? It Happened One Night (1934) and The Silence of the Lambs (1991).

3. Many of the extras were real mental health patients

The film was shot on location at Oregon State Mental Hospital and dozens of the patients at the hospital were drafted in as extras. Somewhat predictably, this didn't always run smoothly and on one infamous occasion a patient jumped out of a third-floor window which had been left open by the film crew. The following day, a waggish newspaper ran the headline: "One Flew Out of the Cuckoo's Nest".

4. There was a hip-hop homage to the film called Insane in the Brain

Swedish hip-hop dance troupe Bounce performed the tactfully titled Insane in the Brain on a UK tour in 2008 and 2009. Perhaps unexpectedly, it received positive reviews, with one newspaper describing it as "Not a performance to miss. Not, indeed, an entertainment to miss." But if, heaven forbid, you did miss it, here's some footage of the production.

5. The Swedes love the film more than any other nation

Not content with the usual run of, say, a couple of months, the Swedes continued to show One Flew Over the Cuckoo's Nest in cinemas for an astonishing 11 years, from 1976 to 1987. Director Miloš Forman said exactly what any director should say on hearing the news: "I'm absolutely thrilled by that . . . it's wonderful."

6. The title of the novel is derived from a nursery rhyme

I confess to having no idea what it all means and nor, I suspect, did Ken Kesey. What I do know is that Chief Bromden quotes these lines from Oliver Goldsmith's tongue-twisting nursery rhyme in the novel after receiving electroshock therapy. They do not, however, make an appearance in the film. Nevertheless, here they are in their entirety:

"Vintery, mintery, cutery, corn,

Apple seed and apple thorn;

Wire, briar, limber lock,

Three geese in a flock.

One flew east,

And one flew west,

And one flew over the cuckoo's nest."

Indeed.

7. Oscar-winning actress Anjelica Huston appears as an extra in the film

This is not the role for which Anjelica Huston will be remembered – after all, she won an Oscar for her performance for Prizzi's Honor (1986) – but if you look closely when the boat returns to the pier following the fishing trip, there she is in the crowd. For many years, Huston was rumoured to be in a relationship with Jack Nicholson.

Anjelica Huston (left) as an uncredited extra in One Flew Over the Cuckoo's Nest

8. The music accompanying the opening and closing credits was performed on a musical saw

Jack Nitzsche was nominated for both an Oscar and a Grammy for his work on the soundtrack to One Flew Over the Cuckoo's Nest.

9. Psychiatrists have never forgiven the film for what it did to the reputation of electro-convulsive therapy (ECT)

Contrary to popular belief, Jack Nicholson did not undergo ECT during filming but the depiction of the procedure was overly dramatic, according to the Royal College of Psychiatrists. "Films such as One Flew Over The Cuckoo’s Nest did for ECT what Jaws did for sharks – the depiction of the treatment in that film is completely over the top, with the patient being held down, writhing in pain, as he is electrocuted," a spokesperson for the organisation has said. "This is not what happens. For a start, during ECT the patient is anaesthetised and given a muscle relaxant – which has been the case since the Fifties – to ensure they feel no pain at all. No one is ever forced to have ECT, and when antidepressant medication isn’t working, it can be life-saving." Nicholson over-acting? Surely not!

This is not what happens during ECT. Apparently.(United Artists/Fantasy Films)

10. Nurse Ratched was Louise Fletcher's first major film role

The actress was selected for the role of the ice-cold nurse ahead of a number of higher profile competitors, including Jane Fonda, Angela Lansbury and Geraldine Page. It was her first major role and she won an Oscar for it but... she was last seen as a guest star in Shameless.